Polarized magnetic switch mechanism



Jan. 19, 1965 A. R. LucAs 3,166,653

PQLARIZED MAGNETIC SWITCH MECHANISM Filed Aug. 50, 1961 3 Sheets-Sheet 1 PEFMHNEN T MAGNET Jan. 19, 1965 Filed Aug. 50, 1961 A. R. LucAs 3,166,653

POLARIZED MAGNETIC SWITCH MECHANISM 3 Sheets-Sheet 2 PERMANENT MAGNET PERMANENT MAGNET PERMANENT PERMANENT MAGNET MAGNET A. R. LUCAS 3,166,653

POLARIZED MAGNETIC SWITCJJH MECHANISM 3 Sheets-Sheet 3 Jan. 19, 1965 Filed Aug. 30, 1961 United States Patent Ofice 3,166,653 Patented Jan. 19, 1965 3,166,653 POLARIZED MAGNETIC SWITCH MECHANTSM Alfred R.' Lucas, Elmwood Park, Ill., assignor, by mesne assignments, to Alfred R. Lucas, Oak Park, lll. Filed Aug. 30, 1961, Ser. No. 135,028 19 Claims. (Cl. 2ML- 93) efficient in operation and can be readilyy and economi-` cally manufactured and installed, particularly in printed circuits; to employ for the pendulum a contact member of such mass and with varying fulcrum point, While moving, that no natural period of vibration or oscillation exists during its movement and therefore it has no adverse effect on the intended operation of the switch due' to any fixed or inherent resonance; to provide completely magnetic energyl activation for operating the contact member from one position to another; to provide a polarizing magnetic field. or fields for biasing the action of rthe contact member; to maintain, temporarily and/or permanently, different contact positions through the influence of the single and/or multiple .static or biased magnetic field and/or fields; to operate, for the greatest eiliciency, dynamic and/or static fields in closed magnetic circuits; to overcome selectively the polarizing magnetic field for effecting movement of the contact member; to eliminate contact bounce; to operate the contact member with a snap action; to employ a pair of'contact members movable into'mutual Contact engagement for completing a circuit; to limit the movement of the two contact memberstoward each other in such manner that movement of only one of the contact members ycannotvcomplete the circuit; to provide a make and break contact arrangement in a new and improved manner; to 'polarize the make and break contact arrangement to bridge normally to the break contact;` and to polarize the make and break contact arrangement to. bridge to either the make or break contact depending upon the character of the last energizationof the switch.

Other objects of this invention will, in part, be obvious and in part appear' hereinafter.

For a more complete understanding of the nature and scope of this invention reference can be had to the following detailed description, taken together with the accompanying drawings, in which:

FIG. 1 is a top planview at a greatly enlarged scale of a switch construction in which one form ofl thepresent invention is embodied.

FIG. 2 is a vertical sectional view taken generally along lthe line 2-2 of FIG. l.

FIG. 3,.is a vertical sectional view taken generally along the line 3-3 of FIG. 2.

FIG. 4 is a horizontal sectional view taken generally along the line 4`4 ofrFIG. 2.

FIGS. 5, 6, 7, 8, 9 and 10 are views, similar to FIG. 2, and showing different embodiments of the invention.

Referring now particularly to FIGS. 1 4 of the drawings, it will be observed that the reference character 10 designates, generally, 'a switch embodying one form of the present invention. As pointed out above the show- Y product.

ing is at a greatly enlarged scale, specific dimensions being referred to hereinafter for illustrative purposes.

The switch 10 comprises a pair of mating case sections 11--11 that may be formed of a suitable insulating material such as glass, ceramic or a phenolic condensation Formed integrally at the ends of the case sections 11-11 are flanges 1212 to provide a space for an energizing coil 13. The coil 13 can be connected for energization either to a source of alternating current or to a source of direct current for the purpose of gen;

erating magnetic iiuX, either alternating or unidirectional of proper polarity, along the longitudinal axis of the case sections 11-11 for a purpose that will be apparent presently. Instead of employing electromagnetic means, such as the coil 13, connected to a suitable current source, the energizing magnetic iiux can be provided by a permanent magnet with proper polarity-which is physically applied to and removed from the case sections 1v1-11 to perform the control operation.

As shown more clearly in FIG. 2 of the drawings,

. angle shaped cores 14 and 15 are employed. They are formedV preferably of high permeability soft iron and thus are capable of conducting current. If desired, the angle shaped cores 14 and 15 can be formed of non electric current conducting magnetic material having a sheath of conducting metal thereon, as described hereinafter. The angle shaped cores 14 and 15 have projecting portions 16 and 17 which constitute first and second circuit terminals, respectively, Ito which connection can be made to an external circuit, such as a printed circuit in which the switch 10 is connected.

The angle shaped cores 14 andv 15 also include sections 18 and 19 that project into the case sections 11-11 and may be suitably secured thereto by adhesive or other means as may be desired. The sections 18 and 19 extend in opposite directions generally parallel to each other in spaced relation and they have at their inner ends V-shaped notches 20 and 21, respectively, in which are pivotally mounted V-shaped sections 22 and 23, respectively, of pendulum contacts 24 and 25 that are formed of electrically conducting magnetic material, such as high permeability softiron. The pendulum contacts 24 and 25 have arms 26 and 27 in overlying relation with contact surfaces 28 and 29, respectively, thereon facing each other. If desired, the various contact surfaces can be plated with copper, silver or the like to improve their conductivity characteristics and reduce the resistance of the circuit between the first and second terminals 16 and `17.

It will vbe observed that the pendulum contacts'24 and 25 are movable from their positions, as shown by full lines, to alternate positions shown by broken lines. In the alternate positions, the contact surfaces 25 and 29 are in engagement and a circuit is completed between the first and second circuit terminals 16 and 17. lt is desirable that this circuit be completed only when both of the pendulum contacts 24 and 25 move to the alternate positions shown by the broken lines.y Accordingly, provision is made for limiting the movement of the pendulum contacts 24 and 25 toward each other so that, in the event that one of them i "is not moved, the circuit cannot be completed by the other contact moving past the alternate position as shown by the broken lines. For this purpose stop shoulders 30 and 31 are provided on the case sections 11-11 and they are so located that, should one or the other of the contacts 24 or 25 not move, then the other of these contacts can only move so far as to engage the respective stop shoulder 30 or 31 in which position the movement will not be suiiicient to cause engagement of the contact surfaces 28 and 29. This arrangement insures that a circuit Will not be completed accidentally through the switch 10 should its movement be accelerated or decelerated at an extremely high rate suilicient otherwise to cause, by inertia and/ or impact, of one or the other of the pendulum contacts l24 or 25 to resist movement or continue movement sumcient to engage the other pendulum contact and complete the circuit therethrough.

With a view to biasing the pendulum contacts 241 and 25 to the positions shown by full lines in FG. 2 of the drawings, permanent magnets 32 and 33 are mounted in the case sections 11 -11. The permanent magnets 32 and 33 have corner notches 34 and 35 for receiving the arms 25 and 27 of the pendulum contacts 24 and 25, respectively. Normally, when no control! magnetic uxis applied either by energization of the coil 13 or by the application of a control permanent magnet, the pendulum contacts 24 and 25 are attracted and held in the positions shownv by the full lines. In these positions the magnetic iiux from permanent magnets 32 and 33 lows through the respective cores .14 and 15 and pendulum contacts 24 and 25. Since the pendulum contacts 24 and 25 tend to assume positions of `minimum reluctance, they are held in the positions shown by full lines although they are free otherwise to move in space 35 within the case sections 11- 11.

. Onthe application of magnetic iiux either by current flow through the winding 13 or from a permanent magnet in an amount suilicient to overcome the attractive forces between the pendulum contacts 24 and 25 and the respective permanent magnets 32 and 33, the pendulum contacts 24 and 25 or more particularly the arms 26 and 27 are attracted toward each other to cause the contact surfaces 2S and 29 to mutually engage and complete the circuit between the rst and second circuit terminals 16 and 17. Upon deenergization of the coil 13 or removal of the permanent magnet creating the control of ilux, just described, the arms 25 and 27 of the pendulum contacts 24 and 25 no longer are attracted toward each other. The mass of the pendulum contacts 24 and 25 is such that they move from one position to the other for each cycle of alternating current used to energize the coil 13. As a result the pendulum contacts 24 and 25 are attracted by the permanent magnets 32 and 33 to the open circuit positions shown by the full lines.

1t will be understood that the movement of the pendulum contacts 24 and 25 into circuit making contact engagement takes place with a snap action. Likewise, on removal of the control magnetic ilux through the angle shaped cores y14 and 15 and the pendulum contacts 24 and 25 in series, they separate with a snap action. The reason for the snap action is that the attractive and repulsive forces of theV permanent magnets 32 and 33 vary inversely as the square of the distances between them and the arms 25 and 27 of the pendulum contacts 24 and 25.

i When a controlled magnetic eld is generatedveither by the energization of the winding 13 or by a permanent magnet, both attractive and repulsive magnetic forces must be considered as simultaneously acting to iniiuence the magnetic state of the arms 26 and 2'7 with their respective contacts 24 and 25. It now will be pointed out that, instead of there being two magneticpoles to be considered, actually six effective magnetic poles must be taken into consideration.

When a control field of any kind inuences the static magnetic `states of the pendulum arms 26 and 2'7, it can be readily understood that such a control iield will impose its poles upon the two permanent magnets 32 and 33 each of which has two poles or a total of four poles. Now when the control iield cornes into being, there are six poles, i.e., three negative and three positive magnetic poles. It is now only necessary to assign polarities for the various parts of the magnetic circuit in order to understand the action that takes place when the control field with its polarities indicated by EB and S polarities is poised magnetically to influence the -jand static or permanent ields generated by the permanent magnets 32 and 33.

. movement but also to have translatory movement rela# Y The polarities have been indicated in FIG. 2 by .-landV to designate the polarities in the various parts of the magnetic circuits resulting from the permanent magnets 32 and 33. When the coil 13 is energized or any other suriciently influencing magnetic field is poised, as repre'- sented by GB and S, in such a manner that the poised lield is in the same direction, magnetically as the-static iields indicated at and and caused by permanent magnets 2 and 33, then, by tracing the polarities it will be apparent that six poles of the three independent magnetic iields are created and their influence on each other to Vcause a resultant snap action will become obvious.

In FIG. 2 the permanent magnet 32 shows a -jor north pole at one end adjacent to its related arm 26 while permanent magnet 33 shows a or south pole adjacent to its related arm 27. Arm 26, being soft magnetic material, has a pole induced therein and it is attracted to its mating permanent magnet 32 while arm 27 has a -lor positive pole induced therein and it is attracted to its mating permanent magnet 33. Permanent magnets 32 and 33 are acting to attract by induction their respective arms 26 and -27 of the pendulum contacts 24 and 25.VK However, when a suiciently influencing eld of a natureVK or source, independent of the static elds of the permanent magnets 32 and 33, is poised upon the arms 26 and 27 to induce polarities as shown thereon at G9 for arm 26 and Q for arm 27, then it can be seen that these polarities are attracting each other or -the juxtaposed portions of the arms 26 and 27 are attracted to each other while the polarities -iand simultaneously are repelling the arms 26 and 27. This occurs only when the 6B and G polarities are quantitively sufficient to dominate, by way of secondary induction, themagnetic states of the arms 26 and 27 which were already polarized inductively by their respective permanent magnets 32 and 33. However, the EB and S polarities by induction must notbe excessive. Only specific control fields allow proper switching as will be apparent hereinafter.

It can be understood that, due to the freedom in opera-` tional movement of the pendulum contacts 24 and 25, bouncing thereof is eliminated because of the dual magnetic latching effect obtained through the use of both attractive and repulsive magnetic forces acting simultaneously to dampen any contact impact.

It has been pointed out that the V-shaped sections 22. and 23 of the pendulum contacts 24 and 25 are movablymounted in the V-shaped notches 20 and 21, respectively.

This mounting is relatively loose with the result that the pendulum contacts 24 and 25 do not pivot, respectively, about the same axis each time they movev but that the axis of movement shifts slightly due to the tendencies of the pendulum contacts 24 and 25 not only to have rotary tive to each other. As a result of this action it is not pos#V sible to develop a resonant condition in the movement of the pendulum contacts 24 and 25 precisely about the same pivot axis each time with the result that the effective length of the radius of each pendulum contact 24 and 25 changes. It can be shown that when this takes place the acceleration changes the resonant period so that any resonance which might exist varies constantly. Since a resonant condition requires that the radius remain con-V stant, it is seen that a resonant condition cannot exist. In other words, a xed pendulum has a period of oscillation but a pendulum whose fulcrumvaries cannot be said to have any constant period of oscillation or resonance. Therefore, the contact arms 26 and 27 have no basic period of resonance in their movement.

As illustrative but not limiting as to the dimensions of the switch 10, it is pointed out that it can have an overall length from the outer end of the angle shaped core 14 to the outer end of the angle shaped core 15 of the order of UAG. The overall width ofthe intermediate Vportion of the case sections 11-11, as viewed in FIG. .3, is of the order of %,2.

The dimensions of the pendulum contacts 24 and 25 and ofthe permanent magnets 32 and 33 correspond to these dimensions for the case sections 11-11.

Instead of employing the two case` sections 11-11 as separate parts, they kcanbe molded into a single unitary structure with the angle shaped cores 14 and 15 and the permanent magnets 32 and 33, leaving the pendulum contacts 24 and 25 free for movement in the space 36 under the control of the various magnetic fluxes as described. In such case the space 36 can be completely closed off and sealed from the atmosphere. In order to improve the arc interrupting characteristics of the pendulum contacts 24 and 25, the space 36 can be evacuated and filled with an arc extinguishing gas, such as sulfur hexafluoride, preferably under pressure. With such a construction it is possiblev to increase materially the amount of current that can be interrupted by the switch 1t).

Because of the relative masses of the pendulum contacts 24 and 25, they are capable of conducting relatively high current with minimum loss due to resistance than is normally the case with similar size devices such as diodes, glass and reed switches, transistors and the like.

Referring now particularly to FIG. 5 of the drawings, it will be observed that the reference character 40 designates, generally, a switch which is somewhat similar to the switch shown in the preceding figures. The switch 4t) includes a pairof case sections, one of which is indicated at 41, it being understood that two mating sections are employed as described hereinbefore for the case sections 11-11. Flanges 42-42 are formed at the ends of the casesections 41 for receiving a coil 43 that can be energized either with alternating current or direct current to generate a control magnetic flux of a magnitudel Vjecting portions 46 and 47 which constitute first and second circuit terminals for the switch 40. The cores 44 and 45 also include sections 48 and 49 which interiit with the case section 41`and areV positioned between it and a like case section as will be understood'readily. The sections 48 and 49 can be secured in the respective case section 41 by any suitable means, such as adhesive means, as may be desired. i

It will be observed that the section 48 of the core 44 has a V-shaped notch 50 for'receiving pivotally an inner edge 51 of a short arm 52 that forms a part of an L-shaped pendulum contact 53 which has its long arm 54 extending in a direction at an angle, preferably 45,Vto the longitudinal axis, indicated by the broken line 55,' and to a transverse axis, indicated by the broken line 55 of the case section 41 or the longitudinal axis of the coil 43 along which it generates the magnetic control flux. This is the most efficient magnetic path. The long arm 54 of the L-shaped pendulum contact 53 has a contact surface 56 that normally is spaced from and is arranged to engage 49'of the core 45 when the L-shaped pendulum contact 53 is moved to the position shown by the broken lines in the manner to be described presently. If desired, the contact surfaces 56 and 57 as well as the portions of the V-shaped notch-50 and of the short arm 5?; which have Contact engagement can be plated with copper, silver or the like to improve their conductivity. In addition, the metallic plating can be extended to the projecting portions 46 and 47 of the cores 44 and 45 to improve their conductivity and reduce the resistance through the switch 40.

In order to bias the L-shaped pendulum contact 53 to the position shown by full lines, a permanent magnet 53 is employed having its longitudinal axis extending at right angles to the long arm 54 and thus at an angle preferably a Contact surface 57 on the juxtaposed side of the section 6 of .45 to the axis indicated by the line 55. It has been found that optimum operating conditions result when this angular relationship is employed with respect to the axis along which the control fiux is applied as indicated by the broken line 55.

On energization of the coil 53 to generate magnetic flux along the axis represented by the line 55 in an amount sulicient to overcome the attractive force between the long arm 54 of the L-shaped pendulum contact 53 and the permanent magnet 58 by creating a magnetic attraction between the long arm 54 and the section 49 of the core 45, the pendulum contact 53 moves with a snap action to the position shown by the broken lines in space 59 within the case section 41 to complete a circuit between the first and second terminals 46 and 47. When the coil 53 is energized with alternating current, this action takes place once each cycle. This same effect can be obtained by bringing a permanent magnet into operative relation with the switch 4i? with its magnetic flux acting generally along the line 55 to the extent described for overcoming the magnetic attraction between the pendulum contact 53 and the permanent magnet 58.

As described hereinbefore, if it is desired to increase the current interrupting ability of the switch 4t), the space 59 can be sealed from the atmosphere, the airy removed and replaced by an arc extinguishing gas, such as sulfur Vhexaiiuoride.

The inclined position of the pendulum contact 53, as shown in FIG. 5, is important. When so located` the major portion of its mass is in alignment with the field of This allows for a morev eiiicient magnetic path of least reluctance to the'control the control flux from the coil 43.

flux.

By employing the L or hook-shaped pendulum contact 53 it is possible to arrange it for free movement in all planes. But the L orhook-shape, as well as the dimensions of the surrounding case, set the limits of free movement and define the physical parameters of such movement; thus the pendulum contact 53 cannot be physically moved or shaken out of contact with its supporting core 44. In order to insure proper positioning of the pendulum contact 53 in the space 59 within the case sections, such as case section 4l, the latter .can be provided with depending ears 60 positioned on opposite sides of the pendulum contact 53. While the depending ears 6i) limit the transverse movement of the pendulum contact 53, they do not interfere with its free movement. Similar ears can be provided for the. other `switch constructions disclosed herein as and where desired. 1

Referring now particularly to the embodiment of the invention shown in FIG. 6 of the drawings, it will be observed that the reference character 63 designates, generally, a switch constructionrthat is similar in some respects to the switch construction shown in FIG. 5 and described hereinbefore. Flanges 65-65 are provided at the ends for vforming an annular space to receive an energizing coil 66 which, as before, can be energized either with alternatvquired to produce the magnetic field for operating the switch 63 in the manner set forth hereinafter.

Mountedy stationarily on the case section 64 and between it and a similar case section (not shown) are magnetic cores 67 and 65 that are formed of electrically conducting magnetic material. Associated with and conductively connected to each of the cores 67 and 68 are terminal strips 69 and 70, respectively, which, with the cores '67 and 68, constitute first and second circuit terminals that are to be connected together under certain operating conditions of the switch 63. The core 67 has a V-shaped notch '71 in one corner into which an inner edge 72 of a short arm 73 that forms a part of an L-shaped or hook shaped pendulum Contact 74vis pivoted. The long arm 75 of the pendulum contact 74 is provided with a contact surface 76 that is arranged to engage a contact surface 77 on the core 68. Thus, when the pendulum contact 74 occupies the position shown by the broken lines, a circuit is completed between the first circuit terminal 69 and the second circuit terminal 7h.

In order to bias the pendulum contact '74 to the closed position shown by the full lines and out of contact engagement with the contact surface 77 on the core 63 a permanent magnet 78 is provided which" generates a reex action to the pendulum contact 74. Like the cores 67 and 68, the permanent magnet 7S is mounted on the case section 64 and between it and a like case section. Underlying the permanent magnet 78 is a terminal strip 79 which extends outwardly beyond the connes of the case section 64 and permits external connection thereto as do the irst and second terminals 69 and 7i).

It will be observed that 4the long arm '75 of the pendulum contact 74 is provided with a contact surface dit on the side opposite the contact surface 76. The contact surface stl is in contact engagement with the inner end of the terminal strip 79 which, with the permanent magnet 78, constitutes the third circuit terminal. Thus, when lthe pendulum contactf74 occupies the full line position attracted by the permanent magnet 7S, a break circuit is completed from the r-st circuit terminal 69 through the pendulum contact 74 to the third circuit terminal 79. This circuit is opened and the make circuit is completed when the pendulum contact 74 is operated to the position shown by broken lines where the make circuit is cornpleted4 from the rst circuit terminal 69 to the second .circuit terminal 70.

With a view to reducing the reluctance of the path for the magnetic ux of the .permanent magnet 78 to the core 67 a core 81 of suitable magnetic material is provided. Thus, when the pendulum contact 74 is in the position shown by the full lines, the principal air gap in the circuit is that which exists through a portion of the case section 64 that is indicated at 82. v

It will be understood that the terminal strips 69 and 70, constituting the first and second terminals, are suitably bonded to the conducting magnetic cores 67 and 68 Iespectively. Also it will be understood that the terminal strip 79, constituting the third circuit terminal, is suitably bonded to the permanent magnet 78 and to the juxtaposed portion of the core S1. All of these parts also are suitably bonded to the case section 64 and the mating case section cooperating therewith. If desired, an encapsulated construction c-an be employed leaving only a space 83 of minimum volume just sufficient to permit movement of the pendulum contact 74 from the break :to the make contact position. v

In operation, as pointed out, the permanent magnet 78 normally attracts the pendulum contact 74 to hold it in the position shown by full lines in FlG. 6. Y understood that the surfaces of the V-shaped notch 71 of the pendulum contact 74 and of the core 63 may be suitably plated with copper, silver or the like to improve their conductivity. Now, when sufficient magnetic ux is generated by the energization of the coil 66 or by bringing into proximity of the switch 6@ a permanent magnet having the requisite strength, the magnetic flux thus provided exerts an attractive force between the core 68 and the pendulum contact 74 in an amount suicient to overcome the attractive force exerted ony the pendulum contact 74 by the permanent magnet 7S. When this relationship exists, the pendulum contact 'i4 moves with a snap action from the position shown by full lines where a circuit is completed between the first circuit terminal and the third circuit terminal to lthe alternate position shownby the broken lines where the circuit is completed from the iirst circuit terminal to the second circuit terminal. The pendulum contact 74 remains in this position as long as the controlling magnetic ux exists. However, as soon as this flux no longer exists 'or is reduced to a value such that the attractive force exerted by the permanent magnet 78 on the pendulum contact 74 is suiicient to attract the It will be 8 latter, it then moves back to the full lines position to complete the circuit previously broken between the lirst circuit terminal and the third' circuit terminal. Y

Referring now particularly to FlG. 7 of the drawings,

it will be observed that the reference character 87 desig" alternating current as may be desired, depending upon the use to which the switch 87 is to be put.

Suitably mounted within the housing formed by the case sections titi is a core 91 of high permeability soft iron having relatively good electrical conducting characteristics. Overlying the core 91 and extending outside of the case section 88 is a terminal strip 92 which, with the core 91, constitutes a first circuit terminal and to which an external circuit can be connected. The core 91 has a V-shaped notc'h93 in one corner for receiving an inner edge 94 of a short arm 95 on an L-shaped or hook shaped pendulum contact 96 and pivotally mounting the same. The pendulum contact 96 has a long arm 97 which is provided with a contact surface 93. formed of relatively good conducting high permeability soft iron and its contact surface 98 is arrangedto engage a contact surface 99 on a permanent magnet 160 that is sutiably mounted in the case section 83 and also is formed of conducting material. Underlying the permanent magnet 10@ is a terminal strip 101 which, with the former, constitutes a second circuit terminal. As shown, the terminal strip 191 extends beyond the case section 88 to permit external connection. When the pendulum contact 96 is operated -to the position shown by the broken lines, a circuit is completed from the first circuit terminal through the `pendulum contact 96 to the permanent magnet 100 and thence to the terminal strip 101.

With a view to holding the pendulum contact 96 in the position shown by the full lines under certain operating conditions, a second permanent magnet 102 is provided in the case sectionV 33j VUn-derlying it is a terminal strip 163 which, with the permanent magnet 162, constitutes a third circuit terminal. It extends outwardly beyond the case section 88 lto facilitate external connection.v The long arm 97 of the pendulum contact 96 has a contact surf-ace 1d!! for engagement with the inner end of the terminal strip 163 so that, when the pendulum contact 96 is in the position shown by full lines, a circuit is completed from the first circuit terminal through the core 91, pendulum contact 9e to the third circuit terminal.

It will be understood that the case sections 88 are such as `to tixedly mount the core 91, terminal strip 92,

Vpermanent magnet 10), terminal strip 101, permanent.

`magnet 19@ can be plated with copper, silver or like to improve the conductivity thereof where a current pathV thereover is required. Instead of employing 'separate case sections 88, the entire assembly can be encapsulated leaving a space 105 that is just suiiicient to permit movement of the pendulum Contact 96 and guide it properly in its movement.

In operation, it is assumed that the pendulum contact 96 is in the position shown by the full lines, Where it is attracted by the permanent magnet 1G32, and that the coil 90 is energized with direct current, for example, having such a polarity and in an amount sutlcient togenerate magnetic iiux through the core 91, pendulum contact 96 in addition t-o the magnetic flux from the permanent magnet 100 and in opposition to the magnetic ux from the mag- The pendulum contact 96 isnet 102. When this control flux is of sutlicient magnitudeA shown by the broken lines because of the force of attrac,

tion between it and the permanent magnet 100i.

When it is desired to return the pendulum contact 96 to the position shown by the `full lines, the polarity of the current flowing through the coil 90 is reversed, thereby reversing the direction of the uX generated thereby. When this flux is of a suiiicient magnitude, it acts in the same-direction as the iux from the permanent magnet 102 and in opposition to the iiux from the permanent magnet100. When it is of suiiicient magnetude so that the resultant attractive force between the permanent magnet 102 and the pendulum contact 96 is greater than the attractive force, which is now changed to a repulsion force, between the pendulum contact 96 and the permanent magnet 100, then the combination of attractive and repulsion forces causes the pendulum contact 96 to move with a snap action and without `bouncing to the position shown by the full lines.

The same effect can be obtained when a permanent magnet is employed for generating the control iiux and it is moved into operative position with respect to the switch 87. It is so positioned with its polarity arranged to eiect the operation of the pendulum contact 96 t-o the alternate position. Then the position of the control permanent magnet is changed to reverse the direction of the control flux and the pendulum contact 96 then operates to the alternate position. This action is known as a iiipflop action since the pendulum contact 96 remains in the last position to which it has been. operated. l

When the coil 90 is energized with alternating current in an amount sufficient to generate the required control magnetic flux, the pendulum contact 96 shifts with. eachy half cycle from one position to theV other.

The flip-ilop switch 87, shown in FIG. 7, is particularly Well adapted as an infinite impedance control for signalling circuits, printed circuits and selective computer matrices and controls. It can be used as a memory, element in expanded and non-integrated bits comprising a memory bit data for storage. I ,Y

The switches 63 and S7, shown in FIGS. 6 and Tof the drawings, are classed, generally, as sub-miniature switches. Preferably they are encapsulated and their size corresponds to thesize of a cube having a dimension of 1A on each side. It will be understood that these dimensions are illustrative and that they may be varied as may be desired.

In FIG. 8 of the drawingsanother switch construction is shown, generally at 108.` The switch 108 is of the magnetic repulsion type and it includes case sections one of which is indicated at 109 and they are similar to the case sections previously described. Flanges 11G-110 are provided for receiving therebetween a coil 111 that can be energized with alternating current or direct current as may be desired. Within the case section 109 is a core 112 of soft iron of high permeability having a projecting portion 113 which constitutes a first circuit terminal. The core 112 at its other end is provided with a U-shaped notch 114 for receiving a rounded lower end 115 of a pendulum contact 116 of soft iron having high permeability. A contact surface 117 is provided on one side ofthe pendulum contact 116 for contact engagement with a contact surface 118 on a depending arm 119 of a terminal strip 120, formed of good conducting material such as copper and constituting a second circuit terminal. The pendulum contact 116 is movable in a chamber 121. When the encapsulated construction is employed, the chamber 121 is sealed from the atmosphere. It can be evacuated and iilled with an arc extinguishing gas to improvethe circuit interrupting capabilities of the switch 108. A permanent magnet 122 is mounted on the case section 109 for the purpose of normally biasing the pendulum contact 116 to the position thereof shown by the full lines. The permanent magnet 122 is positioned between the upper end of the pendulum contact 116 and an extension 123 of the core 112. Below the permanent magnet 12,2 is a section 124 of the case 109. Except for the pendulum contact 116, the remaining parts of the switch 108 are stationarily mounted on the case section 109 and the cooperating case section.

By employing the conventional -land symbols the polarities of the ends of the permanent magnet 122 are indicated. With no external magnetic iield applied, the pendulum contact 116 is held in the position shown by the full lines. Now when the coil 111 is energized in such manner that another magnetic field is set up which is indicated lby the G9 and the S symbols and it is of suiiicient magnitude, the 9 polarity induced in the upper end of the pendulum contact 116 is opposite a like polarity at the juxtaposed end of the permanent magnet 122. As a result the pendulum contact 116 is repelled and moves to the position shown by the broken lines where the circuit is completed between the lirst circuit terminal 113 and the second circuit terminal 120. As soon as the controlled magnetic iield is removed, the pendulum contact 116 no longer is repelled and it is attracted by the sole remaining magnetic ield from the permanent magnet 122 to open the circuit. The pendulum contact 116 then again occupies the position shown -by the full lines. The move-v ments of the pendulum contact 116 in either direction occur with a snap action in view of the inverse square relationship involved in the repulsion and attraction of the magnetic iields involved. Y I

Referring now particularly to FIG. 9 oi the drawings it wili be observed that the reference character 127 designates a switch in which the present invention is embodied, this switch being a lfour terminal, dual pendulum type. The switch 127 includes a pair of case sections of` nonmagnetic material, one of which is indicated at 128, and they were constructed like the previously described case sections. The case section 12S is lprovided with iianges 1129-129 for receiving an energizing coil 130. Mounted within the case actionv 123 are soft iron cores 1.31-132 of high permeability and associated with them are terminal strips 1335-134 which, with the cores 131-132, may be considered tirst and second circuit terminals, respectively. It will be observed that the soft iron cores 131-132 are provided with V-shaped notches 13S-136 for receiving inner edges 137-138 of short arms 139-140 that form parts of L-shaped or hook shaped pendulum contacts 141-142. The long arms 143-144 of the pendulum contacts 141-142 are provided with contact surfaces 145-146 on their juxtaposed sides for completing circuits therethrough when thependulum contacts 141-142, are operated to the positions shown by the broken lines. Shoulders 147-1418011 the case section 128 limit the individual movementy of the pendulum. contacts 141-142 toward each other thereby requiring that both of them move to etect the completion of a circuit therethrough by mutual contact engagement therebetween. As described hereinbefore, the movement of only one of the pendulum contacts 141- 142 to the position shown by the broken lines, Vunaccompanied by like movement of the other, will not effect the completion of the circuit therethrough.

Alsomounted on the case section 128 are permanent magnets 149-150 which are arranged below and above, respectively, the softiron cores 131-132 and normally act to attract the pendulum contacts 141-142 thereto for the purpose of holding them in the positions thereof shown by the full lines. Contact surfaces 151-152 are provided on the opposite sides of the long arms 143-144 k iron cores 131-132 by the d) and 8 signs.

11 i for the purpose of completing circuits through the respective permanent magnets 149-150 to terminal strips 153- 154 which, with'the former, can Vbe considered -to constitute third and fourth circuit terminals.

The pendulum contacts 141-142 are movable within ak confined space 155 within the case section 123. l It will be understood that the entire assembly is encapsulated tothe end that all of the parts, except the pendulum contacts 141-142, are securely ixed in position in the relative locations shown and with the space 155 being entirely closed and capable of being iilled with an arc extinguishing gas, if desired. The terminal strips 13B-134 arenn contact with thecores 131-132 and the contacts strlps 153-154 are in contact engagement with the permanent magnetsl 149-150.

In Vdescribing the operation of the switch 127 it will be .assumed first that the'permanent magnets 149-15@ have the polarities indicated thereon by the land signs. As described, under these conditions, the pendulum con- Y '-t'acts 141-142 are in the positions shown by the full lines :and one circuit is completed between the terminal strip 133, or the irst circuit terminal which is common to the pendulum contact 141, and terminal strip 153, which is indicated as being a part or a third circuit terminal. Liliewise, a circuit is completed from terminal strip 134, constituting part of the second circuit terminal and common to the pendulum Contact 142, to the terminal strip 154, which comprises part of the fourth circuit terminal.

When it is desired to open these two circuits and to complete a lcircuit from the first circuit terminal to the second circuit terminal, the coil 1311 is energized in such manner as to provide the polarities indicated on the soft As a result of these magnetic iields generated by the assumed energization of the coil 13d, the polarities indicated by the G3 and S signs on the pendulum contacts 141-142 will appear. It will be observed that the polarities at the distal ends Vofthe pendulum contacts 141-142 are like the Apolarities of the respective ends of the permanent magnets 149-150. As aresult, the pendulum contacts 141-142 are repelled to the positions shown by the'broken lines where the contact surfaces 14S-1416 engage and cornplete the circuit from the iirst circuit terminal to the second circuit terminal. in doing this the circuits to the third and fourth circuit terminals are opened. As soon as the magentic elds indicated -by the polarties G3 and 9 are removed, the pendulum contacts 141-142 no longer are repelled and they return to their positions shown by the full lines. v

FIG. l shows another embodiment of this invention. Here the switch, indicated generally at 153, is of the dual rocker pendulum type. lt'includes a pair of case sections one of which is indicated at 159, which is formed of nonmagnetic material and corresponds to the case sections described hereinbefore. Surrounding the case section 159 is a coily 1611 which can be energized suitably for controiling the operation of the switch 153. The innerl ends ot the soit iron cores 1151-162 are provided with inclined surfaces 157-163. For example, the surfaces 167-163 may be inclined at an angle away from the vertical through an extent of the order of 2 15. However, it will be understood that this angle of inclination can be changedas desired. The inclined Surfaces 167-168 are provided to furnish a rocker mounting for bar type pendulum contacts 169-1711 of soft iron having high permeability. The pendulum contacts 169-170 are of elongated rectangular cross section and are 'arranged to rock about ulcrum points 171-172 at the lower and upper ends of the inclined surfaces 167-168. Contact surfaces 173-1711 are provided on the juxtaposed sides of the pendulum contacts 169-171) and they are arranged to be engaged to complete a circuit between theiirst and second circuit terminals when the pendulum contacts 169- 17@ are moved to the positions shown by the broken lines. The pendulum contacts 1119-170 are normally held in the positions shown by the full lines by permanent magnets 175-1'76 which are located generally parallel to the soft iron cores 161-162 and extend inwardly from the magnetic shunts 165-166.

Further control of the operation ofthe pendulum contacts 16h-170 can be obtained through the provision of magnetic shunts 177-178. It will be observed that they are positioned in overlapping relation with the permanent magnets -176 and the juxtaposed distal ends of the pendulum contacts 169-170. The operating characteristics of the pendulum contacts 169-170 are varied depending upon the presence or absence of the magnetic shunts 17 7-17 8.

The polarized states of any of the permanent magnets disclosed herein can be changed for various operational functions thus imparting a selective method of control by the direction of the control flux.

The various magnetic cores and contacts disclosed herein as being formed of electrically conducting magnetic material can also be formed of non-electrically conducting magnetic material. Where electrical conducting characteristics are required, the magnetic cores cen be plated with a layer of good conducting metal, such as copper, silver or the like or particles of conducting material can be combined with the magnetic material such as with ceramic type magnetic material.

With the proper ampere turns and polarity providing a unidirectional eld control for the switches disclosed herein, they will not operate when, with all other conditions remaining the same, the polarity is reversed. This characteristic is the basis for good control with a specified direct current power and is particularly the case where the flip-hcp design shown in FIG. 7 is employed and Where alternating current, per se, is not used.

Since certain further changes can be made in the foregoing constructions and diiierent embodiments of the invention can beL made without departing from the spirit and scope thereof, it is intended that all matter shown in the accompanying drawings and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

What is claimed as new is:

`1. A switch comprising, in combination, an electrically conducting magnetic core forming a irst circuit terminal, means forming a second circuit terminal in insulated spaced relation to said firstl circuit terminal, a contact o'felectrically conducting magnetic material mounted on said magnetic core for movement into bridging relation between said rst and second circuit terminals, a permanent magnet on said magnetic core and between it and said contact member to hold the latter out of said bridging relation, land means for causing magnetic flux to traverse said core and contact and generally along the magnetic axis of said permanent magnet in an amount suicient to overcome the attractive fonce between said permanent magnet and said vcontact and move it into said bridging relation.

2. A switch comprising, in combination, a pair of Contact members `of elongated magnetic material in overlying coplanar spaced relation at one end for a substantial portion of their respective lengths, a magnetic core movably supporting cach contact member adjacent the other end, a permanent magnet individual to each contact and cooperating therewith and with the respective mag'- netlc core to attract the respective contact whereby the contacts are held in spaced relation, and means for causing. magnetic flux to traverse said contacts and cores in series in a sufficient amount to overcome the attractive force between each contact vmember and its permanent magnet and cause the former to move toward each other.

3. A switch comprising, in combination, a pair of contact members of elongated magnetic material in overlying eoplanar spaced relation at one end for a substantial portion of their respective lengths, a magnetic core movably supporting each contact member adjacent the other end, a permanent magnet individual to each contact and cooperating therewith and with the respective magnetic core to attract the respective contact whereby the contacts are held in spaced relation, means for causing magnetic flux to traverse said contacts and cores in series in a suicient amount to overcome the attractive force between ch contact member and its permanent magnet and cause the former'to move toward each other, and stop means cooperating with each contact member to limit its movement toward the other contact member to a predetermined position. t

4. A switch comprising, in combination, a 'pair of angle shaped cores of electrically conducting magnetic material with the arms thereof extending in parallel insulated spaced relation and one arm Vof each core having a V-shaped notch facingin a direction opposite to the notch in the corresponding arm of the other core, a pair of pendulum contacts of electrically conducting magnetic material individual to said cores andreach having along one side near one end a laterally extending V- shaped section pivoted in the respective V-shaped notch and a contact face along the opposite side near the other end in juxtaposed overlying relation to the 4contact face of the other pendulum contact, a permanent magnet Within each angle shaped core extending from the other arm thereof toward the respective pendulum contact and acting to attract the same and hold said contact faces in spaced relation, and means for causing magnetic flux to traverse said magnetic cores and pendulum contacts in series in a sufiicient amount to overcome the attractive forces between said permanent magnets and said pendulum contacts and cause the latter to be attracted and engage said contact facesto complete an electric circuit between said cores.

5.-A switch comprising, in combination, a pair of angle shaped cores of electrically conducting magnetic material with the arms thereof extending in parallel insulated spaced relation and one arm of each core having a V-shaped notch facing in a direction opposite to the notchin the corresponding arm of the other core, a pair of pendulum contacts of electrically conducting magnetic material individual to said cores and each having along one-side near one end a laterally extending V`- shaped section pivoted in the respecitve V-'shaped notch and a contact face along the opposite side near the other end in juxtaposed overlying relation to thecontact face of the other pendulum contact, a permanent magnet within each angle shaped core extending from the `other arm thereof toward the respective pendulum contact land acting to attract the same and hold saidcontact forces in spaced relationfmeans yfor causing magnetic flux to traverse said magnetic coresl and pendulum contacts in series in la sufficient amount to overcome the attractive forces between said permanent magnets and said pendulum contacts and cause the latter to be attracted and engage said contactl faces to complete an electric circuit between said cores, and stop means cooperating with each contact to limit the movement thereof toward the other contact to a position where neither ncontact can engage'the other unless each moves toward the other.

6. A switch comprising, in combination, a pair of magnetic cores in spaced relation, a contact member of magnetic material movably mountedwon one of said cores for movement toward the other core, a permanent magnet on said magnetic core and between it and said contact member to hold the latter away from said other magnetic core, and means for causing magnetic ux to traverse said magnetic cores and contact member and generally along the magnetic axis of said'permanent member in an amount sufiicient to overcome the attractive force of said permanent magnet on said contact member and move the latter toward said other core.

7. A switch comprising, in combination, a pair of magnetic cores in spaced relation with one of said cores having a notch, a generally L-shaped contact member of magnetic material having the inner edge of its shorter arm pivoted in said notch whereby said contact member is mounted for movement toward the other core, a permanent magnet cooperating with said one magnetic core and said contact member to hold the latter away from said other magnetic core, and means for causing magnetic fiux to traverse said magnetic cores and contact member and generally along the magnetic axis of said permanent magnet in an amount sufficient to overcome the attractive force of said permanent magnet on said contact member and move the latter toward said other core.

8. The invention, as set forth in claim 6, wherein the magnetic cores are positioned along an axis, the contact member and permanent magnet positioned in angular relation to said axis, and the magnetic flux means acts principally along said axis.

9. The invention, as set forth in claim 8, wherein the contact member and permanent magnet are positioned substantially at right angles to each other and at substantially 45 to the axis in the absence of flux from the magnetic flux means.

10. A switch comprising, in combination, a pair of electrically conducting magnetic cores in insulated spaced relation forming first and second circuit terminals, means forming a third circuit terminal in insulated spaced relation to said first and second circuit terminals, a contactof electrically conducting magnetic material movably mounted on the core forming said first circuit terminal and movable from contact engagement with said means forming said third circuit terminal into contact engagement with said core forming said second circuit terminal, a permanent magnet on said core forming said first circuit terminal and between it and said contact to hold it in bridging relation with respect to said first and third circuit terminals, and means for causing magnetic flux to traversesaid `magnetic cores and contact and generally along the magfirst circuit terminal, means including another permanent magnet forming a third circuit terminal in insulated spaced relation to said rst and second circuit terminals, a contact of electrically conducting magnetic material mounted on said core for movement into bridging relation between said first circuit terminal and either said second or said third circuitterminal with the respective permanent magnet holding said contact in the respective position, and means for causing magnetic fiux to traverse said core and contact in an amount suiiicient to overcome the attractive force between said contact and the permanent magnet attracting it and move it into bridging relation with respect to said second or third circuit terminal as the case may be.

12. A switch comprising, in combination, an electrically conducting magnetic core forming a first circuit terminal, means forming a second circuit terminal in insulated spaced relation to said first circuit terminal, a contact of electrically conducting magnetic material mounted on said magnetic core for movement into bridging relation between said first and second circuit terminals, a permanent magnet on said magnetic core and between it and said contact member to hold the latter out of said bridging relation, and means for causing magnetic fiux to traverse said core and contact and generally along the magnetic axis of said permanent member in an amount sufficient to induce a magnetic pole in the distal end of said contact having a polarity like that of the juxtaposed permanent magnet whereby the attractive force between said permanent magnet and said contact is overcome and the latter is repelled from the former.

13. A switch comprising, in combination, an electrically conducting magnetic core forming a rst circuit terminal, non-magnetic means forming a second circuit terminal in insulated spaced relation to said rst circuit terminal, a contact of electrically conducting magnetic material mounted on said magnetic core for movement into bridging relation between said first and second circuit terminals, a permanent magnet on said magnetic core and between it and said contact member to hold the latter out of said bridging relation, and means for causing magnetic flux to traverse said core and contact in an amount suiiicient to induce a magnetic pole in the distal end of said contact having a polarity like that of the juxtaposed permanent magnet whereby the attractive force between said permanent magnet and said contact ris overcome and the latter is repelled from the former.

14. A switch comprising, in combination, a pair of con tact members of elongated magnetic material in overly ing coplanar spaced relation at one end for a substantial portion of their respective lengths, a magnetic core movably supporting each contact member adjacent the other end and forming first and second circuit terminals respectively, a permanent magnet individual to each Contact and cooperating therewith and with the respective magnetic core to attract the respective contact whereby the contacts are held in spaced relation, said permanent magnets forming third and fourth circuit terminals respectively, and means for causing magnetic flux to traverse said contacts and cores in series in a sutiicient amount to overcome the attractive force between each contact member and its permanent magnet to open the circuits between said iirst and third circuit terminals and cause said contact members to move toward each other to complete a circuit between said `first and second circuit terminals.

15. A switch comprising, in combination, a pair of cores of electrically conducting magnetic material cxtending in parallel insulated spaced relation with the opposing offset ends carrying fulcrums, a pair of pendulum contacts of electrically conducting magnetic material individual to said cores and on one side engaging the fulcrums thereon, each pendulum contact having a contact face along the opposite side in juxtaposed overlying relation to the contact face of the other pendulum contact, a permanent magnet individual to each pendulum contact actingjto attract the same and hold said contact faces in spaced relation, and means for causing magnetic iiux to traverse said magnetic cores and pendulum contacts in seriesin a sufficient amount to overcome the attractive forces between said permanent magnets and said pendulum contacts and cause the latter to be atracted and engage said contact faces to complete an electric circuit between said cores.

'l 16. A switch comprising, in combination, a pair of cores of electrically conducting magnetic material extending in parallel insulated spaced relation Vwith the opposing otfset ends carrying fulcrumsa pair of pendulum contacts of electrically conducting magnetic material individual to said cores and on one side engaging the fulcrums thereon, each pendulum contact having a contact face along the opposite side in juxtaposed overlying relation to the contact face of the other pendulum contact, a permanent magnet individual to each pendulum Vcontact acting to attract the same and hold said conact yengage said contact faces to complete an electric circuit between said cores, and magnetic shunt means overlying the distal end of each pendulum contact and the respective permanent magnet.

17. A switch comprising, in combination, a magnetic core forming a first circuit terminal, means forming a second circuit terminal in insulated spaced relation to said first circuit terminal, a contact of electrically conducting magnetic material mounted on said magnetic core for movement into bridging relation between said iirst and second circuit terminals, a permanent magnet on said magnetic core and between it and said contact member to hold the latter out of said bridging relation, and means for causing magnetic flux to traverse said core and contact and generally along the magnetic axis of said permanent magnet in an amount sufficient to overcome the attractive force between said permanent magnet and said contact and move it into said bridging relation.

18. A switch comprising, in combination, a pair of angle shaped cores of magnetic material with the armsthereof extending in parallel insulated spaced relation and one arm of each core having a V-shaped notch facing in a direction opposite to the notch in the corresponding arm oi? the other core, a pair of pendulum contacts of electrically conducting magnetic material individual to said cores and each `having along one side near one end a laterally extending V-shaped section pivoted in the respective V-shaped notch and a contact face alongfthe opposite side near the other end in juxtaposed overlying relation to the contact face of the other pendulum contact, a permanent magnet within each angle shaped core extending from the other arm thereof toward the respective pendulum contact and acting to attract the same and hold said contact faces in spaced relation, and means for causing magnetic ilux to traverse said magnetic cores and pendulum contacts in series in a sufficient amount to overcome the attractive forces between said permanent magnets and said pendulum contacts and cause the latter to be attracted and engage said contact faces to complete an electric circuit between said cores.

19. A switch comprising, in combination, a pairof magnetic cores in insulated spaced relation forming first and second circuit terminals, means forming a third circuit terminal in insulated spaced relation to said first and second circuit terminals, a contact of electrically conducting magnetic material movably mounted on the core forming said rst circuit terminal and movable from contact engagement with said means forming said third circuit terminal into contact engagement with said core forming said second circuit terminal, a permanent magnet on said corel forming said first circuit terminal and between it and said contact to hold it in bridging relation with respect to said first and third circuit terminals, and means for causing magnetic flux v` to traverse said magnetic cores and contact and generally along the magnetic axis of said permanent magnet in an amount suilicient to overcome the attractive force of said permanent magnet on said contact and move it into bridging relation with respect to said rst and second circuit terminals.

References Cited in the file of this patent UNITED STATES PATENTS l2,275,531 Lakatos Mar. l0, 19,42 2,350,663 Agnew June 6 1944 v2,454,973 Mason NOV. 30, 1948 2,504,101 Reifel Apr. 18, 1950 2,810,039 Every Oct. l5, 1957 2,830,152 Tasker et al. Apr. 8, 1958 2,848,661 Amourig Aug. 19, 1958 2,869,050 Van Urk et al Jan. 13, 1959 2,897,416 Packard July 28, 1959 3,033,956 Juptner May 8, 1962 3,053,953 Braumann Sept. 11, 1962 x/riff!! UNITED STATES PATENT OFFICE CERTIFICATE 0F CQRRECTION Patent No. 3,166,653 January 19, 1965 Alfred R. Lucas lt is hereby certified, that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

ColumnA 13, linev69, and column 14, line 69, for "member",

each occurrence, read magnet column 15, line 10, after "contact" insert and generally along the magnetic axis of said permanent magnet line 49 for "atracted" read attracted Signed and sealed this 22nd day of June 1965.

(SEAL) Attest:

ERNEST W. SWTDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE 0F CQEEECTION Patent No 3 ,166 ,653 January 19 1965 A1fred R. Lucas 1t is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Column. 15 line .69, andY Acolumn 14 line 69 for "member",

each occurrence, read magnet column 15, line 10 after "Contact"` insert 'and genera11y along the magnetic axis of said permanent magnet line 49, for "atracted" read attracted Signed and sea1ed this 22nd day of June 1965.

(SEAL) Attest:

ERNEST w. swIDER e EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A SWITCH COMPRISING, IN COMBINATION, AN ELECTRICALLY CONDUCTING MAGNETIC CORE FORMING A FIRST CIRCUIT TERMINAL, MEANS FORMING A SECOND CIRCUIT TERMINAL IN INSULATED SPACED RELATION TO SAID FIRST CIRCUIT TERMINAL, A CONTACT OF ELECTRICALLY CONDUCTING MAGNETIC MATERIAL MOUNTED ON SAID MAGNETIC CORE FOR MOVEMENT INTO BRIDGING RELATION BETWEEN SAID FIRST AND SECOND CIRCUIT TERMINALS, A PERMANENT MAGNET ON SAID MAGNETIC CORE AND BETWEEN IT AND SAID CONTACT MEMBER TO HOLD THE LATTER OUT OF SAID BRIDGING RELATION, AND MEANS FOR CAUSING MAGNETIC FLUX TO TRAVERSE SAID CORE AND CONTACT AND GENERALLY ALONG THE MAGNETIC AXIS OF SAID PERMANENT MAGNET IN AN AMOUNT SUFFICIENT TO OVERCOME THE ATTRACTIVE FORCE BETWEEN SAID PERMANENT MAGNET AND SAID CONTACT AND MOVE IT INTO SAID BRIDGING RELATION. 